I have driven an SI and ITR and noticed a big difference in VTEC pops when I get into my GSR. I heard there is a butterfly on the intake manifold lowers the tone when VTE hits. Is it possible to bypass this? I was also considering buying a Skunk 2 intake manifold to get rid of it, but if I buy the manifold, where do I run the hoses that used to go to the butterfly? Or does it stay on there? Is there no way to make the VTEC pop louder?

 

what it is is the dual runners. you have one set that is open all the time, and once you hit 5700 the second set opens up. it's supposed to provide more torque in the bottom end. you can't disable it (and i wouldn't) unless you bought a skunk2 intake manifold, which is basically a Type R manifold (single runner) made to fit the B18C1.

 

you are just asking for trouble....it's bad enough i get pulled over cause they think my exhuast is too loud but it is stock...officer...it is just my intake

 

The reason why the si and the itr's vtec is louder is because their vtec engages at a higher rpm. Well with the itr, its more than that, but anyways. I didnt really like the stock vtec point on the gsr either, so i installed a skunk2 manifold and put my pr3 b16 ecu back in. Now vtec engages at 5800, just where i like it. If you want your vtec to "pop" louder then the easiest way would probably be to get a vtec controller and set the vtec up higher, like maybe around where the secondary butterflies open up. One of my friends did this and he seems to enjoy it, not just for the sound though.


[Modified by Civic DX 4dr, 3:17 PM 9/19/2002]

 

Why worry about the VTEC noise?

The VTEC on the GS-R motor is designed with the dual-butterfly manifold in mind. Your VTEC kicks in at 4500rpm and the butterfly opens up at 5600-5800rpms accordingly.

The manifold design on the GS-R is actually good. It boost low end and midrange power - something the B16A and B18C5 have none of.

If you put on the Skunk2 manifold alone it will run like ****. you'd need the right ECU program and even worse, the right TRANNY to make it run right.

The GS-R engine is paired with a taller-geared tranny because it's VTEC kicks in lower. If you drop a Skunk2 mafold on there you'll need an ECU with a 5800rpm VTEC cross or so, then the motor will drop out of VTEC if you keep the longer-geared GS-R tranny.

Does that make any sense?

This is all coming from someone who currently owns a B18C5 and B16A2 hatch and also had a B18C1 in a hatch too.

Get some cams - that will surely make the VTEC stronger and louder if that's what you want.

Lastly:

My GS-R VTEC was really loud at 4500rpm - it made like a hollow "pop" when VTEC hit. It wasn't backed up by a full thoaty VTEC note until the secondaries opened up at 5800rpm or so.

 

With a built GS-R motor, the Skunk2 IM and reprogrammed ECU would be nice and would work well with the stock tranny.

If all you want is noise, well, get a louder exhaust. My B17A1 is too loud sometimes.

 

Good point, i forgot to mention that. Im running a Y21 lsd tranny scavenged from my b16 along with the ecu and i have to say it is a sweet setup. B18c1 + Y21 lsd trans =

 

yeah you got that right. you will hear a distinct crossover point from low to high.

you can disable the secondary butterflies, just plug the vacuum line that leads to the mechanism. if you have enough mods (internal mostly) then you will feel a difference in having the butterflies open all the time, especially with more aggressive cams.

i'm currently running with the butterflies open all the time and i have more low end with the modifications i have done, though it sounds unlikely.

later

 

you could just get ITBs .. ever heard a VTEC switch with ITBs ?

greg

 

i'd like to =D

 

i have a controller and often thought about this, but was worried that it may do damage keeping the primary lobes spinning till up round the 6k mark..wil it?

 

No it won't do any damage. But why do it?

You'll be slower all around...